The field of the invention is convertible sofas and the invention relates more particularly to convertible sofa mechanisms which unfold in three sections from the sofa seat portion.
Most commonly used convertible sofas utilize a foldable mattress which is maintained within the convertible sofa when the bed is folded into its couch configuration. Then when the mechanism is unfolded for use as a bed, the mattress is maintained on the upper surface. Unfortunately, such mattresses, since they need to be folded, must be thin and such convertible sofas are, thus, inherently uncomfortable and are only satisfactory for small children or for emergency use. Also, the forward edge of such convertible sofas, both in the folded sofa configuration or the extended bed configuration, have a hard forward edge which makes it uncomfortable to sit on the forward edge of the convertible sofa or the bed.